Carburetor



Dec. 29 1925- 1,567,171

A. P. PLAUT CARBURETOR Filed August 22, 1921 amend 1 M A7: {-0 in el? .Tda vaw. /W2mmm 4 flttomup Patented Dec. 29, 1925.

PATENT orrice.

UNITED STATES ANTOINE P. PLAUT, or DETROIT, TioriIeAN, ASSIIGEOR or ONE-HALF, To ROBERTS BRASS MANUFACTURING COMPANY, or nnTaoiT, MICHIGAN, A CORPORATION OF MICHIGAN.

CARBURETOR.

Application filed August 2 2, 1921. Serial No. 494,361.

To all whom it may concern:

Be it known that I, ANTOINE P. PLAU'r, a citizen of France, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Carburetors, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates to carburetors and 'has for one of its objects the provision of a carburetor permitting of free flow of the fluids, air and fuel whereby the law relating to the flow of fluids in pipes can be applied and the calibration of the openings and pas sageways can be calculated. Another object is to provide a carburetor in which, by the use of the same law and an adequate construction, can be secured within certain him its a definite proportion of air and fuel for the various speeds of the engine to which the carburetor is applied. Further objects are to provide a carburetor in which the transfer above the throttle of all the fuel drawn through the nozzle at any time and at any speed of the engine will be assured; and to provide a carburetor having an idling chamber for segregating fuel available for the purpose of acceleration.

With these objects in view as well as others, the invention resides in the novel features of construction and combinations and arrange- ;ments of parts as more fully hereinafter set forth.

In the drawings: Figure 1 is a central cross section through a carburetor embodying my invention;

Figure 2 is a top plan view of the nozzle 12 with the choke tube removed;

{ Figure 3 is a section on the line 33 of Figure 1.

The carburetor has the induction passageway 1 and the air inlet passageway 2 connecting laterally into the induction passage- ',way at its lower end. 3 is a choke tube arranged within the induction passageway. i is an emulsifying chamber within the cylindrical enlargement 5 extending from the wall 6 separating the float chamber 6 from the air inlet passageway 2, the emulsifying chamber 4 extending substantially axially of ing 1% in its upper end.

the induction passageway 1 and being located below the choke tube 3. 7 is a well within the wall 6 and coi'r nnunicating with the atmosphere through the aperture 8 at its upper end and with the emulsifying chamber 4 by the vertical series of horizontal air ducts 9, 10, and 11, the well and expansion chamber acting as an acceleration well.

12 is an a'tomizi-ng nozzle extending axially of the induction passageway 1 and having the series of inclined calibrated openings 13 in its periphery arranged substantially opposite the throat or constricted portion of the choke tube and the axial calibrated open- This atomizin'g nozzle has an inside chamber 15 of less cross sectional area than the emulsifying chamber at with which latter the former communicates. 16 is a fuel nozzle extending axially of the emulsifying chamber 4 with its lower end in communication with the float chamber and at its upper end the axial calibrated hole 17. 18 is a plug screwed into an opening in the enlargement 5 and carrying the fuel nozzle 16, which latter extends through the former. This plug terminates below the lower" air duct 11 and carries at its upper end the tube 19 which extends above the upper end of the fuel nozzle and is spaced from the wall of the emulsifying chamber. Both this tube and plug are spaced from the wall of the fuel nozzle to form the idling chamber 20 which will collect fuel emerging from the fuel nozzle, most of the fuel, however, collecting outside the idling chamber 20 within the lower end of the emulsifying chamber 4: and well 7 being thus segregated and available for acceleration in case of the throttlebeing closed and then reopened suddenly. The plug has an intermediate portion of reduced diameter provided with an annular groove 21 and a radial port 22. 23'is the idling tube extending axially of the well 7 and communicating with the inclined by-pass 24 which leads into the induction passageway 1 above the throttle valve 25. This idling tube also communicates with the annular groove 21 through the lateral fuel passageway 26, the groove 27 in the plug 28, the calibrated opening 29 through the wall of this intermediate portion and the axial passageway 30. The plug 28 is at the lower end of the well 7 and has the axial recess 31 in its upper end for engagement by the lower end of the idling tube. 23 is an air vent into the idling tube above the fuel level.

In order to transfer any fuel which might pass out of the atomizing nozzle 12 and drop down along its outer surface to a point above the throttle valve, the upper face 32 of the enlargement 5 is depressed and in communication with the tube 33, the upper end of the tube being in communication with the bypass 25 so that any fuel collecting in this depression will be drawn up through the tube 33 and by-pass 25 and will enter the induction passageway 1 above the throttle valve.

The choke tube 3 is secured in place by suitable means 3% such as set screw and has its lower end of smaller diameter than that of the induction pasageway l to form an air chamber 35 surrounding the constricted portion of the choke tube. This arrangement is similar to that described in my copending application Serial Number -l86,941, filed July 23, 1921.

36 is an adjustable valve for controlling the. quantity of air entering into the by-pass The operation of the carburetor is as follows. When the throttle is in idling position the fuel is conveyed to the induction passageway above the throttle by means of the idling tube 23 which receives its supply from the idling chamber 20 formed by the tube 19 surrounding the supply nozzle 17. hen the throttle is opened wider a sufficient depression is created by the choke tube to draw fuel emulsion from the calibrated orifices 13 and 14, the air forming the emulsion being introduced by reason of the atmospheric inlet 23 which communicates through the well 7 and lateral air duets with the emulsifying chamber -l-. Some of the fuel will not be carried away by the air through the choke tube, especially at the lower engine speeds and will run down the sides of the atomizing nozzle where it will be collected in the depression 32 and conveyed above the throttle through the tube 33 and bypass 25. With the throttle opened still wider, the level of the fuel in the emulsifying chamber will be lowered sufficiently to allow air to be introduced through all of the air ducts and under these conditions practically all of the fuel will be delivered through the calibrated orifices in the atomizing nozzle 16 and conveyed to the engine by the air passing through the choke tube.

From the above description, it will be readily seen that the fuel is conveyed above the throttle valve in three different ways. First, when the engine is running idle, the fuel is conveyed through fuel nozzle 16, the idling chamber 20, lateral passageway 26,

idling tube 23, and bypass 24. Second,

when the engine is running at slow speed,

through the fuel nozzle 16 and atomizing nozzle 12, down the side of the atomizing nozzle into the dished upper surface 32, through the tube 33, and bypass 25. Third, at higher speeds, fuel is conveyed from the fuel nozzle 16, blown through the emulsifying chamber a the atomizing nozzle 12, and carried by the air passing through the choke tube 3.

It is obvious that the upper end of the tube within the emulsifying chamber 4- may be at different heights above or below the upper end of the fuel nozzle 12 depending upon the amount of fuel which it is desired to segregate for acceleration purposes.

The principle involved in this carburetor is the same as that involved in the carburetor disclosed by my Patent No. 1,204,901, issued November 14, 1916 and the same calculations hold true.

The sides of the choke tube throat or restricted portion is determined from the piston displacement of the engine in conjunction with a maximum velocity of air through the throat, determined by previous practice.

The aggregate areas of the atomizing holes may vary from 5 to 10 per cent of the area of the throat, thus allowing the same diameter of the atomizing holes for a Wide range of throat sizes. The aggregate areas of the air ducts is made from 45 to 55 per cent of the aggregate areas of the atomizing holes, thus making a depression in the emulsifying chamber, a certain percentage of what it is in the throat of the choke tube.

What I claim as my invention is:

1. In a carburetor, the combination with an emulsifying chamber, of a calibrated fuel inlet device extending thereinto, a well in communication with the atmosphere, 0. series of vertically spaced lateral passageways connecting said well and emulsifying chamber, an idling tube, a tubular idling chamber surrounding said fuel inlet device and having an open upper end in communication with said emulsifying chamber, and means for placing said idling chamber and idling tube in communication with each other.

2. In a carburetor the combination with a fuel inlet tube having a calibrated orifice therein, of a tubular member surrounding said inlet tube and forming an annular idling chamber, an idling by-pass connected to said idling chamber, an emulsifying chamber surrounding said tubular member, and an atomizing nozzle communicating with said emulsifying chamber.

3. In a carburetor the combination with an induction passage and a throttle therein. of a main fuel nozzle in said induction passage having an emulsifying chamber coinmunicating therewith, an auxiliamwell open to the atmosphere, a series of vertically duction passage above the throttle, and a spaced air ducts between said emulsifying passageway'located below the lowermost of 10 chamber and said auxiliary Well, a fuel said air ducts for connecting the lower end inlet tube extending into said emulsifying of said idling chamber to said idling by-pass A 5 chamber, a tubular member surrounding said tube.

\ inlet tube and extending slightly above the In testimony whereof I affix my signature. same to form an idling chamber, an idling by-pass tube communicating with said in- ANTOINE P. PLAUT. 

